This invention relates to internal combustion engines in general and more particularly to a testing method for a reciprocating piston internal combustion engine, using an angular velocity mesurement about top dead center.
In German Offenlegungschrift 23 50 363, a circuit arrangement for measuring the uniform running of an internal combustion engine in which the individual pistons of a reciprocating engine traverse a predetermined crank angle range about top dead center of the corresponding piston is described. The measurement is performed with the ignition suppressed and the engine driven externally by the starter motor. It gives information regarding the compression of the individual pistons. For this purpose, the times in which the different pistons of the engine traverse the fixed angular range about the top dead center, must be compared with each other or with a standard value.
The known arrangement thus serves to test for one given function of the engine, the compression. In contrast thereto, determining the overall operational fitness of a reciprocating piston engine is of primary importance with the present invention. From economic considerations, there is a need for a measuring method which can provide an overall statement as to whether an engine under test is operating properly or whether it should be tested in further examination steps for individual defects. With methods now in use, all intact test pieces, i.e., engines, are found to be in order only after a series of individual tests. It is more economical to have this preceded by a general test which distinguishes the defective test pieces from the good ones.